Idaho · THREADEX · 1875–2026

Boise, ID

43.567°N, 116.241°W · station BOIthr · 152 years of record
99°F
forecast high · Jul 18

7-Day Forecast

NWS NDFD forecast high temperature for Boise.
98°MON7/1394°TUE7/1497°WED7/1598°THU7/1698°FRI7/1799°SAT7/1898°SUN7/19

This Day in History · Jul 18

Today ranks

#15 / 150
warmest Jul 18 in 150 yrs of record

Hottest Jul 18 ever

106°F
set in 2009

Coolest Jul 18 ever

67°F
set in 1916

Hottest Jul 18 — Year by Year

Every year's high on Jul 18 at Boise. The forecast line shows where today lands; the ringed bar is the hottest on record.
67861061875: 98°F1876: 100°F1877: 99°F1878: 80°F1879: 90°F1880: 98°F1881: 93°F1882: 98°F1884: 80°F1885: 88°F1886: 88°F1887: 88°F1888: 92°F1889: 90°F1890: 96°F1891: 95°F1892: 83°F1893: 101°F1894: 93°F1895: 85°F1896: 98°F1897: 82°F1898: 81°F1899: 102°F1900: 83°F1901: 96°F1902: 84°F1903: 94°F1904: 74°F1905: 90°F1906: 88°F1907: 82°F1908: 83°F1909: 78°F1910: 91°F1911: 93°F1912: 97°F1913: 88°F1914: 93°F1915: 81°F1916: 67°F1917: 96°F1918: 97°F1919: 82°F1920: 97°F1921: 97°F1922: 98°F1923: 90°F1924: 82°F1925: 98°F1926: 97°F1927: 97°F1928: 90°F1929: 88°F1930: 87°F1931: 97°F1932: 92°F1933: 97°F1934: 96°F1935: 95°F1936: 100°F1937: 92°F1938: 99°F1939: 94°F1940: 96°F1941: 92°F1942: 81°F1943: 91°F1944: 96°F1945: 88°F1946: 88°F1947: 94°F1948: 94°F1949: 95°F1950: 90°F1951: 99°F1952: 85°F1953: 92°F1954: 92°F1955: 94°F1956: 92°F1957: 85°F1958: 87°F1959: 98°F1960: 102°F1961: 93°F1962: 78°F1963: 84°F1964: 101°F1965: 90°F1966: 95°F1967: 92°F1968: 85°F1969: 93°F1970: 98°F1971: 86°F1972: 90°F1973: 95°F1974: 101°F1975: 89°F1976: 84°F1977: 94°F1978: 87°F1979: 101°F1980: 83°F1981: 92°F1982: 91°F1983: 91°F1984: 96°F1985: 93°F1986: 90°F1987: 68°F1988: 88°F1989: 99°F1990: 94°F1991: 88°F1992: 96°F1993: 82°F1994: 95°F1995: 93°F1996: 96°F1997: 72°F1998: 99°F1999: 84°F2000: 90°F2001: 81°F2002: 88°F2003: 103°F2004: 104°F2005: 98°F2006: 95°F2007: 97°F2008: 94°F2009: 106°F2010: 96°F2011: 97°F2012: 99°F2013: 100°F2014: 94°F2015: 86°F2016: 95°F2017: 96°F2018: 99°F2019: 87°F2020: 97°F2021: 101°F2022: 90°F2023: 94°F2024: 101°F2025: 97°F99° forecast187520092025

The Numbers

Forecast high · Jul 1899°F
Hottest this date since2024
This-date record106°F
This-date rank#15 of 150
Hottest at any time since2026
All-time record111°F (1898)
Odds to tie/break2.0% (daily)
Period of record1875–2026

Record Book

The hottest and coldest ever recorded at Boise in each calendar month, and for the whole 1875–2026 record — with the year each was set.
MonthRecord HighRecord Low
Jan66°F2024-28°F1888
Feb71°F1992-15°F1989
Mar83°F20265°F1906
Apr92°F189811°F1936
May100°F189722°F1982
Jun110°F201530°F1901
Jul111°F189835°F1986
Aug110°F196132°F1892
Sep104°F202223°F1926
Oct94°F199211°F1971
Nov78°F1999-10°F1896
Dec70°F1939-25°F1990
All-time111°F1898-28°F1888

2026 Records So Far

Records set or tied at Boise so far this year — through Jul 11.

Record Highs in 2026

4 broke
plus 2 tied — daily record highs set this year
Monthly high record this year: Mar (83°F)

Record Lows in 2026

0 broke
plus 0 tied — daily record lows set this year

Hot Streaks

Current run

9 days
consecutive days with a high ≥ 90°F

Longest ever

50 days
record run, ended Aug 22 1875

So far in 2026

17 days
days with a high ≥ 90°F this year

Climate Normals

Normal high & low by month, from Boise's own 1991–2020 record. Today's normal high: 93°F · forecast is +6° vs normal.
Jan: 39°FJan: 25°FFeb: 46°FFeb: 29°FMar: 56°FMar: 34°FApr: 62°FApr: 39°FMay: 72°FMay: 47°FJun: 81°FJun: 54°FJul: 93°FJul: 62°FAug: 91°FAug: 61°FSep: 80°FSep: 52°FOct: 65°FOct: 41°FNov: 49°FNov: 31°FDec: 39°FDec: 25°FJFMAMJJASOND

Sun & Location

Sun & Daylight Today

Sunrise4:16 AM
Sunset7:25 PM
Solar noon11:50 AM
Daylight15h 10m · losing 8 min/wk
Local standard time (no DST), level horizon.

Location

43.57°N, 116.24°W

Nearby Stations

Ontario, OR49 mi NWStanley, ID77 mi NEMcCall, ID91 mi NJerome, ID107 mi SEBaker City, OR117 mi NWChallis, ID120 mi NE

The Last 6 Weeks

Boise's observed daily high for the last six weeks — a white ring marks any day that broke or tied its daily record for that date.
Boise, ID — last six weeks of daily high

2026 So Far

Every day this year against Boise's own record — the record high, the normal, and the full span ever seen. A shareable look at where the year stands.
Boise, ID — 2026 daily high trace
Download year chart

Every Day Since 1875

Each cell is one day's high at Boise, coloured by temperature — 152 years of record, so heat waves read as warm streaks and cold snaps as blue.
Boise, ID daily high heat map 1875–2026

Days Above the Mark

How many days a year hit a given high at Boise — counted through Jul 18 each year, so you can see whether 2026 is running hot. Pick a threshold:
17 days ≥90°F so far in 2026 — tied for the 41st most in 152 years. Normal for this point: 13. Record: 34 in 2021.

Share Card

A ready-to-share summary of Boise's outlook — post it, or link this page.
Boise, ID hot share card
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part of Weather Trader · supported by Substack Subscribers · data: NWS NDFD forecast + NOAA/ACIS ThreadEx records · updated 2026-07-13T12:58:10Z
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